If this judgment stands, it is incredible. A world-leading judgment that goes well beyond the ridiculous half one-tenth measure that the EU recently imposed on Apple, which at first resulted in Apple cutting their 30% cut of sales down to just 27%, and after some pushback, Apple oh-so graciously agreed to let developers keep 95% of their money for purchases that don't use any Apple infrastructure. This is definitely better than that, because it bans those fees.
That said, this is a decision of a single judge of the Federal Court. It will undoubtedly be appealed to the High Court, and who knows how it will end up. A good start, but there's a long way to go before the headline is truly accurate.